The National Cancer Institute (NCI) reports that there are 23,000 new oral-cancer cases each year. The NCI says 5,400 people die each year from oral cancer. Harari says lip cancer represents only a fraction of new cases each year because the disease is not accurately reported. In addition, few people think about protecting their lips from sun.

Harari says people don't realize that they should spread sunscreen on their lips as well as on their face and body when out in the sun. He recommends sunscreen with 30 SPF or more.

"The bottom lip is more likely than the upper lip to develop cancer because it gets more sun," Harari said. "Cancer on the upper lip is rare and can be more lethal than cancer of the lower lip."

People living in warm climates are at greater risk of getting lip cancer, technically identified as skin cancer. Harari says smokers, people who chew tobacco and spend a lot of time in the sun have an even higher risk.

Lip Cancer Symptoms

Symptoms of lip cancer include:

An irritated area that can look and feel like chapped lips or a cold sore

Crusty patches on the lips

Bleeding

Lip pain

Harari says anyone with symptoms that last more than three or four weeks should see a doctor. He says when a lip malignancy is caught early, the cure rate is 90 percent or more. Harari believes early detection has improved over the last few years.

"For the past 10 years or so, dentists have been doing routine oral-cancer screenings for their patients. That has accounted for an improvement in early detection," said Harari.

Harari estimates that every year, UW oncologists see a dozen patients who have been referred from dentists following an oral screening.